diff --git a/third_party/mesa/MesaLib/src/egl/main/eglconfig.c b/third_party/mesa/MesaLib/src/egl/main/eglconfig.c
index ca28b5f91816e649dbb758b7d8b0c0cefba6ffa0..1c97e4287eb7b5645b8991f97d98b08996eb9cb6 100644
--- a/third_party/mesa/MesaLib/src/egl/main/eglconfig.c
+++ b/third_party/mesa/MesaLib/src/egl/main/eglconfig.c
@@ -242,7 +242,7 @@ _eglValidateConfig(const _EGLConfig *conf, EGLBoolean for_matching)
 
    /* check attributes by their types */
    for (i = 0; i < ARRAY_SIZE(_eglValidationTable); i++) {
-      EGLint mask;
+      EGLint mask = 0;
 
       attr = _eglValidationTable[i].attr;
       val = GET_CONFIG_ATTRIB(conf, attr);
diff --git a/third_party/mesa/README.chromium b/third_party/mesa/README.chromium
index a405e3c9f3248b043e53ee541b48d7ca67a4281f..4f51b8708b930dd41b65eb8619f601ebe10d1d81 100644
--- a/third_party/mesa/README.chromium
+++ b/third_party/mesa/README.chromium
@@ -73,3 +73,5 @@ Later modifications (see chromium.patch):
 
 - Guarded all usage of EGL_Y_INVERTED_NOK with EGL_NOK_texture_from_pixmap
   so that it can be compiled against standard EGL 1.4 headers.
+  
+- Initialized uninitialized mask variable in eglconfig.c line 245.